A spokeswoman for the police said: "In order to recover all weapons, gather evidence and ensure public safety whilst all weapons were recovered specialist trained search officers remained at the address for approximately four weeks together with officers on scene management.

"The overtime spend for this period was approximately £160,000."

It is understood the number of weapons seized by police ran into three figures.

A vast amount of ammunition was also found.

A 63-year-old man from Norfolk, arrested on 16 July on suspicion of selling or transferring a firearm to a person without a certificate, has been bailed until 27 August.